Ok, this is extremely confusing. I have two WordPress sites running, a test one and my real one. I make all changes and updates to my test one first then I apply the same changes to my real site. So basically they are mirror sites.
However, on one my page of my real site, I'm simply trying to add the iframe code for Google Calendar but every time I click on save the iframe code simply disappears in thin air and my calendar is gone. I don't know why, it was working fine for weeks now. The interesting thing, it works fine on my test site. I simply go to create new page, click on the HTML tab, paste my cose, click on publish and voila! It's there.